Duke researchers come close to perfect invisibility cloak

Duke scientists have perfected the real-life invisibility cloak, but, contrary to what Stephen Colbert said, the Duke Quidditch team will not be able to take advantage of it.

The cloaking device uses meta-materials to split electromagnetic waves and channel them around an object so that they appear on the other side, hiding the object from sight. Meta-materials are man-made compounds that exhibit properties not found in nature.

Nathan Landy, an electrical and computer engineering graduate student in his fourth year, recently went viral for designing a revolutionary cloaking device for microwave frequencies. The development of the cloak may enable new advances in transformation optics and the improvement of optical devices. Landy has been featured on the Colbert Report, Forbes Magazine, Fox News and on countless blogs. The findings were first published in the November edition of Nature.

“[This cloak] is probably the best that can be done,” David Smith, a co-author of the paper describing the device, said. “If you make it larger, the waves get absorbed. Anything more is a long way away.”

Landy initially joined the project because he was interested in the ways meta-materials transform and objects distort light.

Smith, William Bevan professor of electrical and computer engineering, noted Duke had already created a working cloak back in 2006. The new meta-material has allowed the researchers to cloak a centimeter-scale cylinder from microwaves.

Smith has worked on the cloaking device since 2006, when John Pendry, an electrical engineering professor at Imperial College London, joked that they could use his math on the subject to create an invisibility cloak. Smith pursued the project in response to Pendry’s comment.

“It was mentioned on the Colbert Report and that’s all you can hope for,” Landy said.

Although the term ‘invisibility cloak’ has been popularized by the Harry Potter series, there are still significant differences between the fiction and reality. The real-life device can only conceal a device from one angle, Landy said.

The cloak is shaped like a metal square, and all of the materials can be found in a desktop computer, he added. The untrained eye is unable to see anything disappear in a demo of the device.

Despite the recent breakthrough, there is still room for improvement, Smith noted.

The project is supported by the Office of Naval Research and Army Research Office. The military has plans to implement the device, but Landy declined to specify how it would use it.

Correction: An earlier version of this article indicated that a quote by Landy was actually said by Smith. The Chronicle regrets the error.